It is sometimes necessary to inspect certain areas that are inconvenient and/or time-consuming to access. For illustrative purposes, the inspection of storm and sewer pipes will be described, although the scope of the present invention is by no means limited to this application. Most municipalities contain a vast network of storm and sewer pipes. Periodically, these pipes must be inspected for problems such as cracks, blockage, build-up, and root infiltration. If a problem is detected, detailed images must be obtained to facilitate planning to remedy the situation. To this end, it is common for an invasive device such as a pipe crawler or push camera to be introduced into the pipe to perform the inspection and, at the same time, to obtain details of any problem encountered.
Although effective in obtaining detailed images, using a pipe crawler is inconvenient and requires a great deal of time to set up and operate, even if no problems are discovered. Setting up a pipe crawler involves first interrupting the water flow ahead of the pipes to be inspected and diverting it with a pump system, then cleaning all the pipes and finally introducing the pipe crawler in the pipe, which in itself requires the entering of a man through a manhole. In other words, much work is needed to obtain detailed information regardless of whether a problem exists.
Other methods for routine inspection involve using a camera with a powerful zoom fitted to the lower end of a mast. The camera and mast are lowered into a manhole until the camera reaches one of the sewer pipes. There, the camera is made to zoom in and out to obtain images of the interior of the pipe. Suspending the camera and mast by hand requires much manipulation and becomes rapidly tiring. Mounting the camera and mast to a vehicle is far more convenient. The operator can drive up to the area to be inspected, position his vehicle over a manhole, lower the camera into the manhole until it reaches the pipe to be inspected, and start collecting data.
Known vehicle mounted inspection cameras have a major drawback however. Since the camera and mast are lowered vertically from the vehicle, they are not capable of adequately reaching lateral sewer pipes that are offset from the manhole. Although most manholes are positioned squarely above the lateral conduits that they access, some manholes are substantially offset, generally because of an obstacle being in the way. In many municipalities, approximately 10% of the underground piping network does not receive proper routine inspection with known equipment because the pipes are offset from the manholes that access them.
Therefore, there is a need for a routine inspection system that is both convenient for the operator, cost effective, and that allows reaching substantially all conduits radiating from a manhole, including those that are offset.